Generally, two major types of sealing machine exist. One is a stationary sealing machine, and the other is a portable sealing machine. Both types have advantages and disadvantages. Stationary sealing machines are used most often for large packages and provide better sealing performance but consume lots of power. Portable sealing machines are used most often as kitchen appliances to seal smaller packages and consume less power. However, sealing machines with the advantages of both types are not available in the market. Therefore, people either have to buy both or accept the inherent disadvantages of the one they purchase.
Because portable sealing machines are small and have a small heat sealing region of 1˜2 centimeters, they are easy for people to grip and squeeze. However, sealing a large plastic bag smoothly and efficiently can be challenging.
Conventional sealing machines generally comprise a base, an optional power module or power cord, a cover, a heating module and optional over-current protection. When the cover is pressed toward the base, power is provided to the heating module, and the heating module generates heat to seal a plastic bag. The protection circuit will deactivate the heating module to prevent the sealing machine from overheating and damaging the sealing machine. However, it only protects the sealing machine itself but not a person operating the sealing machine. For example, if a child plays with the sealing machine and does not notice or understand that the heating module is activated, she or he may be burned.